Air-separator



J. STUHTEVANT:

AIR SEPARATOR.

APPLICATION FILED OCT. 7. 1919.

Patented. July 26, 1921.

2 SHEETS-SHEE'I' ITIT GJZI OI U IZM & SEW

I AA/01.1297

THOMAS J. STURTEVANT, OF WELLESLEY, MASSACHUSETTS, A SSIGNOR TOSTUBTE-VANT MILL COMPANY, OF BOSTON, MASSACHUSETTS,

CHUSETTS.

Specification or Letters latent.

A CORPORATION OF MASSA- AIR-SEPARATOR.

Patented July 26', 1921.

Application filed October 7, 1919. Serial No. 329,094.

To all (whom it may concem Be it known that I, THOMAS J. STURTE- \ANT, acitizen of the United States, residing at Wellesley, in the county ofNorfolk and State of Massachusetts, have invented an Improvement inAir-Separators, of which the following description, in connection withthe accompanying drawings, is a specification, like characters on thedraw in s representing like parts.

he invention to be hereinafter described relates to air separators, andmore particularly to separators of the type disclosed in my copendin Iapplications Serial No. 297,291, filed ay 15, 1919, a d Serial No.319,646, filed August 25, 1919.

This type of separator comprises outer and inner casings forming innerand outer chambers and provided with a fan for prod'ucing a circulatingair current which movesupward in the inner chamber and downward in theouter chamber. The materials to be graded are introduced into the innerchamber t rough the top thereof and strike a rotary istributer whichunder the influence of centrifugal force throws the materials outwardinto the path of the rising current of air. Lighter particles are liftedthereby up to the fan, pass through the fan, and thence downward throughthe outer chamber, whereas, the heavier particles gravitate downwardthrough the rising current of air in the inner chamber. The fineparticles are discharged through one passage, and the coarser particlesare discharged through another passage.

In grading of materials, there is a tendcncy for the lighter particlespassing downward through the outer chamber to be carried by thecirculating air current back into the inner chamber. If the finerparticles are returned to the inner chamber in substantial amount, ofcourse, the efliciency of the separator is materially reduced.

The rotary fan tends to produce a whirling current of air downwardthrough the outer chamber, and the centrifugal force of this air currenttends to carry the particles outward against the inner surface of theouter chamber, so that they tend to pass downward past the lower openingbetween the outer and inner chambers a substantial distance therefrom.The whirl and centrifugal eflect diminish as the current approaches saidopening, and the force thereof in some instances is sufficient to givecentrifugal effect adequate to prevent entrance of particles back intothe inner chamber. One of the purposes of the present invention,therefore, is to provide simple and eflicient means for increasing thewhirl effect of the air and thereby increasing the vcentrifugal forcethereof, more effectively to prevent return of the lighter particlesfrom the outer chamber into the inner chamber. In carrying this featureof the invention into practical effect, in the present instance, the fanis inclosed in a chamber and one or more guides or conduits of a spiralor helical character are provided, comma-- nicating with the fan chamberand the outer chamber so as to deliver the air current into the outerchamber with a pronounced whirl of the air current creating acentrifugal force opposite the lower opening between the outer and innerchambers sufficient to cause the lighter particles to pass downwardalong or sufliciently adjacent to the inner surface of the outer wall ofthe outer chamber to greatly reduce the percentage of particles carriedby the air current into the inner chamber.

Another purpose of the invention is to provide a valve or gate for eachof the air conduits which may not only serve to vary the strength of theair current for classification of materials of varying character, butalso may serve to contribute to the direction of the whirling aircurrent delivered from the air conduit orair conduits.

In my said application Serial No. 297 ,291, a series of vanes or valvesare provided at the lower opening between the outer and inner chamberswhich serve to promote a whirl effect of the air and also to vary thestrength of the air current for classifyingmaterials of varyingcharacter. Another purpose of the present invention is to provide an airconduit or air conduits such as described, which may be so related tothe vanes referred to, as to cooperate therewith desirably in theproduction of the whirling.

air current. In other words, the air conduit or conduits may be sorelated to said vanes as to direct the whirling air currents in such amanner as'to be received bysaid vanes and directed by the latter fromthe outer to the inner chamber.

secured thereto With :the aforesaid and other objects in view, thecharacter of the invention will be bestunderstood by reference to thefolldwing description of one good form thereof shown in the accompanyingdrawings, wherein:

Figure 1 is a vertical section taken on line 1-1 of Fig. 2 through theseparator shown herein as embodying the invention;

Fig. 2 is a plan of the separator;

Fig. 3 is a perspective View of a portion of the separator; and

Fig. 4 is a sectional detail of a latch device for holding the airconduit gate in dif ferent positions of adjustment. 4 v

Referring to the drawings, the separator shown therein as one good formof the invention, comprises a support. in the present instance, in theform of a ring 1 (Fig. 1) having feet 3 adapted to be secured by bolts 5to beams 7 or other appropriate supportin means.

ounted on aflange 9' of the foundation ring is an outer casing 11 forthe outer chamber 13, said casing having a base ring 15 provided with aninternal flange resting on the foundation rin flange 9 and vdetachablyby screw bolts 17. The outer casing has a shell 19, in the presentinstance of cylindrical form, with its lower edge riveted to the basering 15 and its upper edge riveted to a top ring 21'. A head 23 issecured to the top ring and is provided with eyes 25 adapted to beconnected to a suitable tackle which may be used for lifting the outercasing from the foundation ring when desired.

Within and spaced from the outer casing is an inner casing 27 for theinner chamber 28 and having an upper conical shell 29 and a lowerconical shell 31. The'adjacent ends of said shells are secured to rings33 connected by through bolts 35. These rings are shouldered to receivea circular baflie plate 37 which may be made in sections and be made ofstronger and more durable material than the upper and lower shells 29and 31. The construction is such that on release of the through bolts35, the baffle plate 37 may readil be removed and another substitutedthere or.

Encircling the lower conical shell 31 is a cylinder 39 having its upperedge secured to the lower ring 33 and its lower edge secured to a ring41. Projecting outward from thering 41 are feet 43 having socketsresting on the upper ends of posts 44 which have their lower ends seatedin sockets 45 on brackets 47 projecting radially inward from thefoundation ring 1.

A conical casing 49 is secured to and depends from the foundation ringand has a port at the lower end thereof through which the fines aredischarged, as more fully heremafter descrlbed,

-ner and outer chambers.

To conduct the coarser particles from the inner chamber,a mouth orcollar 51 has its lower edge secured to an upstanding flange of an anglering 53'secured tothe inner ends of the brackets 47' referred to.Interposed between said angle ring 53 and said brackets is the outwardlyprojecting flange of a conical collar 55. Depending from the latter is aconical] casing 57 communicating with a spout 59'thaving a delivery endprojecting through the fines discharge casing 49 referred to. r

The shells 29 and 31 and the intermediate plate 37 divide the outercasing into a sep arating chamber and a collecting chamber.

The materials to be graded may be introduced into the separator througha hopper 61 secured to the head 23. Projecting downward from the hopperis a feedtube 63 for conducting the materials to therotarydistributerdevice.

The rotary distributer device, in the present instance. comprises a head65'having a table 67 with vanes 69 rising from a peripheral portionthereof and surmounted by a. ring 71. Depending from the edge of saidtable is an apron 73, and rising from and tween the vanes 69 and dropthence onto the annular dish. The hood 87 will serve to de- A taperedflect the materials down onto said dish. The dish is rotated with thetable, and therefore. i

centrifugal force will carry the materials outward in the dish to theupstanding flange which will deflect the same upward into the path ofthe rising air current in theinner chamber. L

The dish and hood may be secured togkthe sleeve 75 referred to, indifferent positions of adjustment. To accomplish this, thehood ring 85may 88 threaded to a portion 89 of the sleeve 75, the parts of said ring88 being clamped to said sleeve by bolts 91 entered through lugs 93projecting outward from the parts ofsaid ring.

The construction is such that on release of said. bolts the dish andhood may be 'verti cally adjusted with respect to the table and fan asdesired. and then may be secured by tightening said bolts.

Suitable means may be provided to produce the circulation of air throughthe in This means, in the present instance, is in the form of a fan 95have a split or two part'ring iao having a hub 96 secured to the upperend of the sleeve 7 5 and long blades 97 project mg outward from saidhub.

uitable means may be provided for ro- Said vertical shaft may be drivenby a bevel gear 113 thereon meshing with a bevel gear 115 on ahorizontal shaft 117 journaled in a bearing 119 carried by said casing109 and in a bearing 121 carried by the foundation ring 1. At the outerend of said horizontal shaft is a pulley 123 adapted to be driven by abelt from any suitable source of power.

The construction is such that the table, dish, hood, sleeve and fan maybe readily rotated by means of the simple transmission described. Thefan will create a circulation of air through the inner and outerchambers which may flow in the general direction inwhirling air currentdelivered by the condicated by the tail arrows in Fig. 1-.

The fan may be inclosed in a chamber 125 separated from the outerchamber 13 by an annular plate or partition 127 detachably secured bybolts to the outer shell. This plate may have a central opening 129registering with the upper end of the upper conical shell 29 of theinner casing. The construction is such that the fan will draw the air upthrough the inner chamber through the opening 129 into the fan chamber.

As stated, one of the purposes of the invention is to provide means forproducing a pronounced whirl eflect of the air current downward throughthe outer chamber so as to produce a centrifugal force suflicient tocause the lighter particles to move downward along or adjacent to theinner surface of the outer wall of the outer chamber. To accomplishthis, in the present instance, one or more air guides or conduits 131are provided, in the present instance, two being shown, but the numbermay be varied according to conditions as desired. Each of these airconduits may be of general helical or spiral form, and may be secured onor adjacent to the outer casing 19 referred to, externally or internallythereof. In the present instance, these conduits are secured to saidcasing externally thereof, and have upper ends communicating with thefan chamher through inlet openings 133, in the pres-- ent instance,substantially diametrically opposed, and said conduits have lower outletopenings 135 communicating with the outer chamber, in the presentinstance, at substantially diametrically opposed points. The shape ofthe conduits may vary according to conditions as desired, but in thepresent instance of the invention, they are of general rectangular crosssection and gradually reduced in width progressively downward from theirinlet to their outlet openings, with a nozzle effect to increase thevelocity and whirl effect of the air current delivered from theconduits.

The construction is such that the air will be forced by the fan outwardthrough the upper inlet openings, thence downward through the conduitsthrough the outlet openings which are so formed as to deliver the aircurrent in relatively thin streams into the outer chamber. These streamswill tend to cling to the inner surface of the outer casing 19, and willhave a pronounced whirl or helical path of move-.

ment which will produce a centrifugal force effect on the particlescarried in the whirling air current, andcause said particles to passdownward close to the inner surface of said outer casing. As a result,said particles will be substantially prevented from entrance through thelower opening to be described, between theouter and inner chambers.

It is desirable to vary the strength of the duits according to thecharacter of the materials to be separated. To accomplish this, in thepresent instance, eachof the conduit outlet openings 135 may be providedwith a gate or valve 137 mounted on a hinge shaft 139 extending upwardthrough the head of the outer casing, where it receives a crank 141provided with a handle 143 containing a latch 145 (Fig. 4) presseddownward by a coil spring 147, and adapted to cooperate with a series ofholes 149 in an arcuate plate 151 mounted on the casing head. The latchhas a head 153 on the upper end thereof, the

construction beingsuch that the latch head 153 may be pulled upwardagainst the resistance of the coil spring 147, and then the and then thegate may be secured .by entrance of the latch 145 into one of the holes149. Thus, the gate may be set in different positions of adjustment tovary the amount of the outlet opening and the strength of the aircurrent delivered therethrough. The gate also serves as a deflectorwhich will contribute to direction of the air current from the outletopening along the inner surface of the outer casing 19.

The whirling air current on leaving the openings 135 will move downwardand thence through the openings 155 back into the inner chamber.Suitable means may be provided to vary the strength of the air currentpassing through this opening, and

to contribute to or promote the whirl of the air current? This means, inthe present instance of the invention, comprises a seriesvalves or vanesare connected by links 163 with arms 165 projecting radially from anadjusting ring 167 mounted on the upper angle ring 159., One of the arms165 may be longer than the others and be connected by a rod 169 to ascrew 171 threaded in the hub of a hand wheel 173 located externally ofthe outer casin 19.whereit is conveniently accessible. 6n rotation'otthe hand wheel the screw 171 will be adjusted in the hand wheel hub, andwill thereby adjust the rod 169 longitudinally, and slide or adjust thering 167 rotatively on the angle ring 159, and said adjusting ring willoperate through the links 163 to open and close the valves any extentdesired.

These valves or vanes and the adjusting means therefor may be similar tothe construction disclosed in my said application Serial No. 319,646.

The direction of said valves or vanes is 7 such that the whirling aircurrent delivered from the conduits will be received by said valves orvanes and deflected thereby from the outer chamber into the innerchamber, and said valves or vanes will desirably contribute to' thepromotion of the whirl effect of the air produced by the conduits. Theoutlets 135 for the air conduits are located adjacent to, and in thepresent instance, a short distance above said valves or vanes, therelation thereof being such that a pronounced whirling effect of the airis produced as it passes downward from the conduit outlets to theopening 155 between the outer and inner chambers. As a consequence, acentrifugal force is produced sufficient to cause the particles carriedby the whirling air current to tend to cling to and pass downward alongthe inner surface of the outer casing 19 remotely from the opening 155between the outer and inner chams bers. As a consequence, the lighterparticles are substantially prevented from being carried by the aircurrent back into the inner chamber, and efiicient separation of thematerials to be graded is accomplished.

The head 23 of the outer casing may be provided with a large man-hole175 detachably secured by clips 177, the construction being such thatthe man-hole may be removed to permit convenient access to the interiorof the casing.

The operation of the separator will be readily understood. The materialsare de-. livered through the hopper 61 and feed tube 63 to the rotarydistribute-r which throws the materials outward and upwardly into thepath of the current of air rising in the inner chamber. The lighterparticles are'carried upward by the air current past the fan through thefan chamber, and thence whirl downward through the conduits into theouter chamber. The lighter particles carried by this whirling aircurrent pass downward, without entering the inner chamber, through theconical casing 49, and are discharged thereby. The heavier particles, onthe other hand, gravitate downward through the air current rising in theinner chamber, pass through the collar 51, through the conical casing.57 h and are discharged through the spout 59. The general path of theair current is indicated by the tail arrows, and the general paths ofthe lighter and heavier particles are indicated by the plain arrows inFig. 1.

The adjusting devices for the conduit gates and the adjusting devicesfor the deouter and inner chambers are located externally of the outercasing of the separator, where they are conveniently accessible for thepurpose'of setting of said gatesor valves or vanes in any positiondesired, for the purposeof producing the most efficient grading effect.

It will be understood that the invention is not limited to the specificembodiment shown, and that various deviations may be made therefromwithout departing from-the spirit and scope of the appended claims.

What is claimed is i 1. An air separator, comprising in oom bination, acasing having therein an inner chamber and a divided outer chambercommunicating with the inner chamber, a fan in one of the divided outerchambers for circu' lating the air current up through the inner chamber,means to introduce materials to be graded into the inner chamber in thepath of said vair current, andspiralguide means leading from the fancontaining chamber to the other outer-chamber to di- 115 root the aircurrent from the fan into'the latter chamber while the air currentcontmues its general whirling direction, there- .by to, producecentrifugal force to throw the particles within the air current outward.120 I chamber and a divided outer chamber com- 123 municating with theinner chamber, a fan in one of the divided outer chambers for, cir--- vculating the air current up through the inner chamber, meansto'introduce materials" to be graded into the inner chamber in the 180fleeting vanes at the opening between the path of said. air current, andspiral guiding means for deflecting the whirling air current produced bythe fan, laterally to the plane of rotation of the fan into the otherouter chamber to whirl about the same, thereby to produce centrifugalforce to throw the particles within the air current outward away fromthe air entrance to the inner chamber,

3. An air separator, comprising in combination, a casing having thereinan inner chamber and a divided outer chamber communicating with theinner chamber, a fan in one of the divided outer chambers forcirculating the air current up through the inner chamber, means tointroduce materials to be graded into the inner chamber in the path ofsaid air current, and inclined guide means for leading the whirling aircurrent produced by the fan from the tan chamber to the other outerchamber and in a direction laterally to the plane of rotation of thefan, thereby to transfer the whirling current from one divided chamberto the other and to produce centrifugal force to throw the particleswithin the air current outwardly away from the (air entrance to theinner chamber, a

4. An air separator, comprising in combination, a casing having outerandinner chambers therein with an opening between them, a fan for producingan air current traveling in a circuit through said chambers, means tointroduce materials into the inner chamber in the path of the aircurrent to be graded thereby,'and spiral guide means for conducting theair current from the fan and laterally to its plane of rotation towardthe openin between said chambers to promote a whirl of the air current,thereby to produce centrifugal force to throw the particles in the aircurrent outward away from said opening so that they will not enter theopening. I 5. An air separator, comprising in combination, a casinghaving outer and inner chambers therein with an opening between them, a;fan for producing an air current traveling in a circuit through saidchambers, means to introduce materials into the inner chamber in thepath of the air current to be raded thereby, inclined means forconductmg the air current from the fan and laterally to its plane ofrotation toward the opening between said chambers to promote a whirl ofthe air current, thereby to produce centrifugal force to throw theparticles in the air current outward away from said opening so that theywill not enter the openmg, and adjustable means for varying the strengthand direction of the air dlscharged from said inclined means. i

6. An air separator, comprising in combination, a casing having chamberstherein, with an opening between said chambers,

ber past said opening a substantial distance from the latter.

7. An air separator, comprising, in combination, a casing having thereinan inner chamber and a divided outer chamber communicating with theinner chamber, a fan so for circulating the air current up through saidinner chamber, means to introduce materials to be graded into the innerchamber in the path of said air current, said outer chamber having aninlet opening in one divided portion and an outlet opening in the otherdivided portion, and a spiral conduit extending between andcommunicating with said openings for receiving the air current and thelighter particles carried thereby, so and for directing the same into aportion of the outer chamber.

8. An air separator, comprising in combination, a casing having thereinan inner chamber and a divided outer chamber communicating with theinner chamber, a vertical shaft within the casing, a fan within one ofthe divided chambers and operated by said shaft to circulate the aircurrent through the chambers, a distributer within the inner 10c chamberand operated by said shaft to introduce the materials to be graded intothe path of the air current, and inclined guide means for directing thewhirling air current produced by the tan, laterally to the plane ofrotation of the fan and into the other divided chamber to whirl aboutthe same, thereby to produce centrifugal force to throw theparticleswithin the air current outward away from the communication between the 10 outer and inner chambers.

9. An air separator, comprising in combination, a. casing having outerand inner chambers therein with an opening between them, means forcirculating 21,11 311 current throu h said chambers, means to introducematerials to be graded into the inner chamber'in the path of said aircurrent, means extending from said air current circulating means towardsaid opening for promoting a whirl of the air current and lighterparticles in their transit from the inner chamber to the outer chamber,and angular-1y adjustable means for varying the strength and directionof'the whirling air currents.

10. An air separator, comprising in com- ,1 bination, a casing havingouter and inner chambers therein with an opening between them, a fan forcirculating an air current through said chambers, means to introducematerials to be graded into from the outer to bination, a casing havingouter bination, a casing having outer and inner chambers therein with anopening between them, a fan for circulating an air current through saidchambers, means to-introduce materials to be graded into the innerchamber in the path of said air current, an inclined conduit betweensaid fan and opening to receive the air current and the lighterparticles carried thereby and conduct the same into said outer chamber,an adjustable gate for varying the strength of the air current deliveredthrough said conduit, and a series of vanes at the opening between saidchambers for directing tllGg air current the inner chamber.

1%. An air separator, comprising, in combination, a casing having outerand inner chambers therein with an opening between them, a tan forcirculating an air current throu h said chambers, means to introduce theinner chamher in the path of said air current, an inclined conduitbetween said fan and 0 ening to receive the air current and the lig terparticles carried thereby and conduct the same into said outer, chamber,an adjustable gate for varying the strength at the air current deliveredthrough said conduit, a series of vanes at the opening between saidchambers for directing the air current from the butter to the innerchamber, and means to angularly adjust said vanes further to control thestrength oi the air current.

13. An air separator, comprising, in comchambers therein with an openingbetween. them, a series of vanes at said opening, a fan for circulatingthe air current through said opening past said van'esinto said innerchamber, spirally disposed guide means for directing the air currentfrom. the fan through the outer chamber t ward said vanes, andadjustable gate means to vary the streng'h of the, air current forgrading materials or varying character.

14. air separator, comprising, in combination, a casing having outer andinner chambers therein with an opening between them a series of vanes atsaid opening, a fan orcirculating theair current through said openingpast said vanesinto said inner chambcr,'spirally disposed guide meansfor directing the air current from the fan through the outer chambertoward said vanes, adjustable means cooperating with I ber, means to andinner said spiral guide means for varying the strength of the aircurrent, and adjustable means for varying the angles of said vanesfurther to vary the strength of the air current.

15. An air separator, comprising, in. combination, a casing having outerand inner chambers therein with an opening between them, a series ofvanes at said opening, a fan for circulating the air current throughsaid opening past said vanes into said'inner chamber, spirally disposedguide means for directing the air current from the fan to the outerchamber in'the form of a stream traveling circumferentially about theouter chamber, adjustable meanscooperating with the spiral guide meansfor varying the strength andifdirection of the air current delivered tothe outer chamber, and adjustable means for varying the angles of saidvanes to vary the direction amount of air passing through said opening.

16. An air separator, comprising, in combination, a casing, separatingand collecting chambers therein having an opening affordingcommunication between said chambers, a rotary distributerin theseparating chamdeliver materials to be graded to the rotary distributerthat they may be thrown outward in the separating chamber under theiniiuence of centrifugal force, a fan for causing an air current tocirculate through said chambers with upward movement in theseparatingchamber and downward movement in the collectingchamber, aseries of vanes in the opening between the chambers for promoting awhirl of the air passing through the opening between said vanes, andvalve means for regulating the strength of the air current.

17. Anair separator, comprising, in combination, a casing havingseparating and collecting chambers therein provided with an openingaffording communication between, said chambers, a rotary distributor inthe separating chamber, means to deliver materials to be graded to therotary distributer that they may be thrown outward thereby in theseparating chamber, a fan for causing an air current to circulatethrough said chambers, adjustable means in the path of the air currentreturning from the collecting chamber to the separating chamberforp'romoting a whirl of the air current and varying the strength of theair current thereat, and valve meansadjustable further to regulate thestrength of'the air current.

18. An air separator, comprising, in com-,

bination, a casing provided with separating and collecting chambershaving provision to permit an air current to circulate through saidchambers with upward movement in the. separating chamber and downwardmovement in the collecting chamber, a fan for creatmgseid air current,means to introv duce materials to be graded into the path of the airmoving upward in, the separating chamber, valve means in the path of theair current entering the collecting chamber from the separating chamberadjustablyto regulate the strength of the air current, and means in thepath of the air current returning from the collecting chamber to theseparating chamber having provision for promoting whirl of the aircurrent and regulating the strength of the air current.

19. An air separator, comprising, in combination, a casing provided withseparating and collecting chambers having provision to allow anairvcurrent to circulate through said chambers with upward movement inthe separating .chamber and downward movement in the collecting chamber,a fan for creating the air current and causing the same to Whirl, meansto deliver materials to be graded in the path of the upward moving airin the separating chamber, adjustable means in the path of ,the aircurrent entering the collecting chamber from the separating chamber toregulate the strength of the air current, and adjustable means in thepath of the air current returning from the collecting chamber to theseparating chamber to regulate the strength of the air current.

20. An air separator, comprising, in combination, a casing provided withseparating and collecting chambers having provision to permit an aircurrent to circulate through said chambers with upward movement in theseparating chamber andv downward movement in the collecting chamber, afan for creating the air current and causlng the same to whirl, means todeliver materials to be graded into the path of the air current movingupward in the separating chamber, means in the path of the air currentpassing from the separating chamber to the collecting chamber adjustablyto regulate the strength of the air current, and means in the path ofthe air current returning from the collecting chamber to the separatingchamber for promoting whirl of the air current.

In testimony whereof, I have signed-my name to this s ecification.

' THO ASv J. STURTEVANT.

